Threads

Joinable_Detached_thread/joinable_example.c

@@ -0,0 +1,111 @@
+/*
+ * =====================================================================================
+ *
+ *       Filename:  joinable_example.c
+ *
+ *    Description:  
+ *
+ *        Version:  1.0
+ *        Created:  07/03/24 04:17:21 PM IST
+ *       Revision:  none
+ *       Compiler:  gcc
+ *
+ *         Author:  YOUR NAME (), 
+ *   Organization:  
+ *
+ * =====================================================================================
+ */
+
+#include <stdio.h>
+#include <stdlib.h>
+#include <pthread.h> /* For working with POSIX threads */
+#include <unistd.h>  /* For pause() and sleep() */
+#include <errno.h>   /* For using Global variable errno */
+
+void *
+thread_fn_callback(void *arg) {
+
+    int th_id = *(int *)arg;
+
+    free(arg);
+
+    int rc = 0;
+
+    while(rc != th_id ){
+
+        printf("Thread %d doing some work\n", th_id);
+        sleep(1);
+        rc++;
+    }
+
+    int *result = calloc(1,sizeof(int));
+
+    *result = th_id * th_id;
+
+    return (void *)result;
+}
+
+void
+thread_create(pthread_t *pthread_handle, int th_id){
+    
+    pthread_attr_t attr;
+    
+    int *_th_id = calloc(1, sizeof(int));
+    *_th_id = th_id;
+
+    pthread_attr_init(&attr);
+
+    pthread_attr_setdetachstate(&attr,
+            PTHREAD_CREATE_JOINABLE
+            /* PTHREAD_CREATE_DETACHED */);
+
+    pthread_create(pthread_handle,
+                    &attr,
+                    thread_fn_callback,
+                    (void *)_th_id);
+
+
+}
+
+/* These thread would find the square of the
+ * argument passed onto it */
+pthread_t pthread2;
+pthread_t pthread3;
+
+int 
+main( int argc, char **argv ){
+
+    void *thread_result2 , *thread_result3;
+    thread_create(&pthread2, 10);
+    thread_create(&pthread3, 2);
+    
+    printf("main fn blocked on pthread join for thread with "
+        "th_id = 2\n");
+
+    pthread_join(pthread2, &thread_result2);
+    
+    if( thread_result2 ){
+
+        printf("Return result from thread 2 = %d\n",
+                *(int *)thread_result2);
+        free(thread_result2);
+        thread_result2 = NULL;
+    }
+
+     printf("main fn blocked on pthread join for thread with "
+        "th_id = 3\n");
+
+    pthread_join(pthread3, &thread_result3);
+    
+    if( thread_result3 ){
+
+        printf("Return result from thread 3 = %d\n",
+                *(int *)thread_result3);
+        free(thread_result3);
+        thread_result3 = NULL;
+    }
+
+
+
+    return 0;
+}